MDSCs in infectious diseases: regulation, roles, and readjustment

Many pathogens, ranging from viruses to multicellular parasites, promote expansion of MDSCs, which are myeloid cells that exhibit immunosuppressive features. The roles of MDSCs in infection depend on the class and virulence mechanisms of the pathogen, the stage of the disease, and the pathology associated with the infection. This work compiles evidence supported by functional assays on the roles of different subsets of MDSCs in acute and chronic infections, including pathogen-associated malignancies, and discusses strategies to modulate MDSC dynamics to benefit the host.

The Microbiome and Genitourinary Cancer: A Collaborative Review

CONTEXT

The recent discovery of the existence of a human genitourinary microbiome has led to the investigation of its role in mediating the pathogenesis of genitourinary malignancies, including bladder, kidney, and prostate cancers. Furthermore, although it is largely recognized that members of the gastrointestinal microbiota are actively involved in drug metabolism, new studies demonstrate additional roles and the potential necessity of the gastrointestinal microbiota in dictating cancer treatment response.

OBJECTIVE

To summarize the current evidence of a mechanistic role for the genitourinary and gastrointestinal microbiome in genitourinary cancer initiation and treatment response.

EVIDENCE ACQUISITION

We conducted a literature search up to October 2018. Search terms included microbiome, microbiota, urinary microbiome, bladder cancer, urothelial carcinoma, renal cell carcinoma, kidney cancer, testicular cancer, and prostate cancer.

EVIDENCE SYNTHESIS

There is preliminary evidence to implicate the members of the genitourinary microbiota as causative factors or cofactors in genitourinary malignancy. Likewise, the current evidence for gastrointestinal microbes in dictating cancer treatment response is mainly correlative; however, we provide examples where therapeutic agents used for the treatment of genitourinary cancers are affected by the human-associated microbiota, or vice versa. Clinical trials, such as fecal microbiota transplant to increase the efficacy of immunotherapy, are currently underway.

CONCLUSIONS

The role of the microbiome in genitourinary cancer is an emerging field that merits further studies. Translating microbiome research into clinical action will require incorporation of microbiome surveillance into ongoing and future clinical trials as well as expansion of studies to include metagenomic sequencing and metabolomics.

PATIENT SUMMARY

This review covers recent evidence that microbial populations that reside in the genitourinary tract-and were previously not known to exist-may influence the development of genitourinary malignancies including bladder, kidney, and prostate cancers. Furthermore, microbial populations that exist at sites outside of the genitourinary tract, such as those that reside in our gut, may influence cancer development and/or treatment response.

Redundant and Distinct Roles of Secreted Protein Eap and Cell Wall-Anchored Protein SasG in Biofilm Formation and Pathogenicity of Staphylococcus aureus

Chronic and fatal infections caused by Staphylococcus aureus are sometimes associated with biofilm formation. Secreted proteins and cell wall-anchored proteins (CWAPs) are important for the development of polysaccharide-independent biofilms, but functional relationships between these proteins are unclear. In the present study, we report the roles of the extracellular adherence protein Eap and the surface CWAP SasG in S. aureus MR23, a clinical methicillin-resistant isolate that forms a robust protein-dependent biofilm and accumulates a large amount of Eap in the extracellular matrix. Double deletion of eap and sasG, but not single eap or sasG deletion, reduced the biomass of the formed biofilm. Mutational analysis demonstrated that cell wall anchorage is essential for the role of SasG in biofilm formation. Confocal laser scanning microscopy revealed that MR23 formed a rugged and thick biofilm; deletion of both eap and sasG reduced biofilm ruggedness and thickness. Although sasG deletion did not affect either of these features, eap deletion reduced the ruggedness but not the thickness of the biofilm. This indicated that Eap contributes to the rough irregular surface structure of the MR23 biofilm and that both Eap and SasG play roles in biofilm thickness. The level of pathogenicity of the Δeap ΔsasG strain in a silkworm larval infection model was significantly lower (P < 0.05) than those of the wild type and single-deletion mutants. Collectively, these findings highlight the redundant and distinct roles of a secreted protein and a CWAP in biofilm formation and pathogenicity of S. aureus and may inform new strategies to control staphylococcal biofilm infections.

What every endoscopist should know about decontamination

Carbapenemase-resistant Enterobacteriaceae (CRE) has been implicated in an alarming increase in the incidence of endoscopy-associated infections and deaths worldwide. Public Health England acknowledges that the rapid spread of CRE bacteria poses an increasing threat to public health and modern medicine here in the UK. As endoscopists, we assume that the endoscope we are handed has been appropriately decontaminated, but how many of us can honestly say that we understand the process and the pathway by which the instruments we use are reprocessed? Do we understand the associated risks if the pathway fails and our part in supporting the teams responsible for this critical role? Successful decontamination of endoscopes is everyone's business, and this article outlines what every endoscopist should know about decontamination.

Clinical review of liver hydatid disease and its unusual presentations in developing countries

Human hydatid cyst disease is an international public health issue that particularly affects the developing countries. In this article, we discuss the epidemiology of hydatid disease in third world countries, the life cycle of echinococcus granulosus and how to make the clinical diagnosis of the disease, including laboratory tests and imaging modalities as well as uncommon presentation of this entity that we have encountered at the American University of Beirut Medical Center (AUBMC). We emphasize on the new World Health Organization classification of hepatic echinococcosis with examples from our clinical practice at AUBMC, and finally we describe the treatment, including medical and interventional therapies.

The emerging role of epigenetic modifiers in repair of DNA damage associated with chronic inflammatory diseases

At sites of chronic inflammation epithelial cells are exposed to high levels of reactive oxygen species (ROS), which can contribute to the initiation and development of many different human cancers. Aberrant epigenetic alterations that cause transcriptional silencing of tumor suppressor genes are also implicated in many diseases associated with inflammation, including cancer. However, it is not clear how altered epigenetic gene silencing is initiated during chronic inflammation. The high level of ROS at sites of inflammation is known to induce oxidative DNA damage in surrounding epithelial cells. Furthermore, DNA damage is known to trigger several responses, including recruitment of DNA repair proteins, transcriptional repression, chromatin modifications and other cell signaling events. Recruitment of epigenetic modifiers to chromatin in response to DNA damage results in transient covalent modifications to chromatin such as histone ubiquitination, acetylation and methylation and DNA methylation. DNA damage also alters non-coding RNA expression. All of these alterations have the potential to alter gene expression at sites of damage. Typically, these modifications and gene transcription are restored back to normal once the repair of the DNA damage is completed. However, chronic inflammation may induce sustained DNA damage and DNA damage responses that result in these transient covalent chromatin modifications becoming mitotically stable epigenetic alterations. Understanding how epigenetic alterations are initiated during chronic inflammation will allow us to develop pharmaceutical strategies to prevent or treat chronic inflammation-induced cancer. This review will focus on types of DNA damage and epigenetic alterations associated with chronic inflammatory diseases, the types of DNA damage and transient covalent chromatin modifications induced by inflammation and oxidative DNA damage and how these modifications may result in epigenetic alterations.

Mechanistic insights and therapeutic opportunities of antimicrobial chemokines

Chemokines are a family of small proteins best known for their ability to orchestrate immune cell trafficking and recruitment to sites of infection. Their role in promoting host defense is multiplied by a number of additional receptor-dependent biological activities, and most, but not all, chemokines have been found to mediate direct antimicrobial effects against a broad range of microorganisms. The molecular mechanism(s) by which antimicrobial chemokines kill bacteria remains unknown; however, recent observations have expanded our fundamental understanding of chemokine-mediated bactericidal activity to reveal increasingly diverse and complex actions. In the current review, we present and consider mechanistic insights of chemokine-mediated antimicrobial activity against bacteria. We also discuss how contemporary advances are reshaping traditional paradigms and opening up new and innovative avenues of research with translational implications. Towards this end, we highlight a developing framework for leveraging chemokine-mediated bactericidal and immunomodulatory effects to advance pioneering therapeutic approaches for treating bacterial infections, including those caused by multidrug-resistant pathogens.

Evaluation of Tagetes patula (Asteraceae) as an ecological alternative in the search for natural control of the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

The cattle tick Rhipicephalus microplus is a great sanitary problem and causes huge losses to livestock, being a vector of important diseases. The aim of this work was to verify the action of plant-derived material obtained from Tagetes patula on the life cycle of R. microplus, as well as to analyze the action of these extracts on ovary cells of engorged females. In the Adult Immersion Test, the crude ethanolic extract (Tp_EtOH) showed an efficacy of 99.2% (LC₅₀ = 18.60 mg mL^-1). From the repellency test, it was found that both the Tp_EtOH and essential oil were 100% efficient on the larval stage. In addition, in the Larval Package Test, a mortality of 98.37% was obtained with Tp_EtOH (LC₅₀ = 3.798 mg mL^-1). From the microscopic analysis of ovary cells, morphological changes in the chorion and cytoplasm of oocytes were observed, with vacuolization around the germinal vesicle and disorganization of the pedicular cells, suggesting an interference in the normal embryogenic formation of the larvae. These results demonstrate that T. patula extracts interfere at all stages of development of the ixodid, from eggs to adults forms, and have a pronounced repellent effect. In addition, the results of the cytotoxicity assays performed on keratinocytes, as well as previous information on oral and dermal acute toxicity (LD₅₀ > 4000 mg kg^-1), attest that T. patula can be a safe alternative for ectoparasitic control, representing an alternative for development of a formulation used to help control populations of ticks in the field.

A thermostable chitinase from the antagonistic Chromobacterium violaceum that inhibits the development of phytopathogenic fungi

The biocontrol activity of some soil strains of Chromobacterium sp. against pathogenic fungi has been attributed to secreted chitinases. The aim of this work was to characterize biochemically a recombinant chitinase (CvChi47) from C. violaceum ATCC 12472 and to investigate its effects on phytopathogenic fungi. CvChi47 is a modular enzyme with 450 amino acid residues, containing a type I signal peptide at the N-terminal region, followed by one catalytic domain belonging to family 18 of the glycoside hydrolases, and two type-3 chitin-binding domains at the C-terminal end. The recombinant enzyme was expressed in Escherichia coli as a His-tagged protein and purified to homogeneity. The native signal peptide of CvChi47 was used to direct its secretion into the culture medium, from where the recombinant product was purified by affinity chromatography on chitin and immobilized metal. The purified protein showed an apparent molecular mass of 46 kDa, as estimated by denaturing polyacrylamide gel electrophoresis, indicating the removal of the signal peptide. CvChi47 was a thermostable protein, retaining approximately 53.7% of its activity when heated at 100 °C for 1 h. The optimum hydrolytic activity was observed at 60 °C and pH 5. The recombinant chitinase inhibited the conidia germination of the phytopathogenic fungi Fusarium oxysporum and F. guttiforme, hence preventing mycelial growth. Furthermore, atomic force microscopy experiments revealed a pronounced morphological alteration of the cell surface of conidia incubated with CvChi47 in comparison to untreated cells. Taken together, these results show the potential of CvChi47 as a molecular tool to control plant diseases caused by these Fusarium species.

Chemical Profile and Biological Activities of Essential Oil from Artemisia vulgaris L. Cultivated in Brazil

Essential oil from the leaves of Artemisia vulgaris L. (Compositae) cultivated in Brazil was investigated for its chemical composition and biological activities including antibacterial, antifungal, and anthelmintic. The constituents of essential oils isolated by hydro-distillation were examined by GC-MS and a total of 18 components were identified. The essential oil was dominated by oxygenated sesquiterpenes (44.4%), sesquiterpene hydrocarbons (33.3%), and oxygenated monoterpenes (16.6%). Caryophyllene (37.45%), germacrene D (16.17%), and humulene (13.66%) were the major components. The essential oils from A. vulgaris showed bactericidal and fungicidal properties against Staphylococcus aureus and Candida albicans, respectively. Anthelmintic activity against Haemonchus contortus was absent in this essential oil. Altogether above results indicate that essential oils from A. vulgaris can be used for various medicinal purposes.

Effects of Sexual Network Connectivity and Antimicrobial Drug Use on Antimicrobial Resistance in Neisseria gonorrhoeae

Contemporary strategies to curtail the emergence of antimicrobial resistance in Neisseria gonorrhoeae include screening for and treating asymptomatic infections in high-prevalence populations in whom antimicrobial drug–resistant infections have typically emerged. We argue that antimicrobial resistance in these groups is driven by a combination of dense sexual network connectivity and antimicrobial drug exposure (for example, through screen-and-treat strategies for asymptomatic N. gonorrhoeae infection). Sexual network connectivity sustains a high-equilibrium prevalence of N. gonorrhoeae and increases likelihood of reinfection, whereas antimicrobial drug exposure results in selection pressure for reinfecting N. gonorrhoeae strains to acquire antimicrobial resistance genes from commensal pharyngeal or rectal flora. We propose study designs to test this hypothesis.

Physicochemical and biological properties of novel chlorhexidine-loaded nanotube-modified dentin adhesive

A commercially available three-step (etch-and-rinse) adhesive was modified by adding chlorhexidine (CHX)-loaded nanotubes (Halloysite®, HNT) at two concentrations (CHX10% and CHX20%). The experimental groups were: SBMP (unmodified adhesive, control), HNT (SBMP modified with HNT), CHX10 (SBMP modified with HNT loaded with CHX10%), and CHX20 (SBMP modified with HNT loaded with CHX20%). Changes in the degree of conversion (DC%), Knoop hardness (KHN), water sorption (WS), solubility (SL), antimicrobial activity, cytotoxicity, and anti-matrix metalloproteinase [MMP-1] activity (collagenase-I) were evaluated. In regards to DC%, two-way ANOVA followed by Tukey's post-hoc test revealed that only the factor "adhesive" was statistically significant (p < 0.05). No significant differences were detected in DC% when 20 s light-curing was used (p > 0.05). For Knoop microhardness, one-way ANOVA followed by the Tukey's test showed statistically significant differences when comparing HNT (20.82 ± 1.65) and CHX20% (21.71 ± 2.83) with the SBMP and CHX10% groups. All adhesives presented similar WS and cytocompatibility. The CHX-loaded nanotube-modified adhesive released enough CHX to inhibit the growth of S. mutans and L. casei. Adhesive eluates were not able to effectively inhibit MMP-1 activity. The evaluation of higher CHX concentrations might be necessary to provide an effective and predictable MMP inhibition. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res B Part B, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 868-875, 2019.

Presence of carbapenem-resistant bacteria in soils affected by illegal waste dumps

The carbapenem-resistant bacteria (CRB) are currently at the top of the WHO priority list of bacteria that pose the greatest threat to human health. Considering that soil is one of the important environments for the emergence of antibiotic-resistant bacteria, we isolated and quantified cultivable CRB in soils across Croatia, including ones affected by illegal dumps.We cultivated CRB at two temperatures, distinguishing between the intrinsically resistant CRB (37°C, mostly Stenotrophomonas spp.) and the ones that are presumably human-associated and clinically relevant (42°C, Acinetobacter sp., Enterobacteriaceae, Burkholderia spp.). Our study demonstrated that distinguishing between the two offers a better insight into the diversity of CRB in the environment. The ones cultivated at 37°C were found in almost all soil samples, while the presumably clinically relevant ones were absent from uncontaminated pasture and grassland, indicating that human-associated CRB are unlikely to be found in soils spared from anthropogenic influence.

Test sensitivity of a commercial serine protease digestion kit for the detection of Trichinella spiralis and Trichinella pseudospiralis larvae in pig muscle

The reference method for Trichinella detection at meat inspection is the magnetic stirrer method (MSM) utilising HCl-pepsin for pooled sample digestion. Due to availability and quality issues with pepsin, alternative digestion methods are being offered, such as the Priocheck Trichinella AAD kit (T-AAD), based on serine endopeptidase digestion. In this study the T-AAD kit was compared to the reference method. Minced pork samples were spiked with T. spiralis muscle larvae (ML) with- and without capsule or T. pseudospiralis ML, and analysed with both tests. Test results of individually spiked test samples were analysed by generalised linear modelling. The T-AAD test kit was comparable to the reference method for the qualitative detection of T. spiralis in pigs, but not quantitatively. Overall, 94% of spiked T. spiralis were recovered using MSM against 75.2% when using T-AAD (p < 0.0001). Using the MSM 80.0% of spiked T. pseudospiralis were recovered against 20% with the T-AAD (p < 0.0001). Based on our experience with the T-AAD kit, we strongly recommend validating the method on site prior to introduction into routine diagnostic laboratories, but this will not alleviate the poor test sensitivity of the T-AAD for the detection of T. pseudospiralis.

Microbial species and biodiversity in settling dust within and between pig farms

The airborne fungal and bacterial species present in pig farm dust have not been well characterised even though these bioaerosols are known to cause inflammation and other airway maladies. In this study, the microbial species and composition in airborne dust within and between pig farms were investigated. Passively sedimenting dust from six pig farms were collected using electrostatic dust collectors. The bacterial and fungal species were identified using matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and next generation sequencing (NGS). Dust samples taken within the same stable section revealed high resemblance and stability. Constrained statistical analysis of the microbial community compositions indicated that the types of stable did not appear to have a great effect on the bacterial and fungal β-diversity. In contrast to this, the farm from which samples were taken appeared to have the greatest effect on the bacterial β-diversity, but this trend was not observed for the fungal β-diversity. The most common bacteria and fungi according to NGS data were anaerobes typically associated with the pig intestinal tract and yeasts respectively. Bacterial sedimentation varied at a rate between 10³ and 10⁹ CFU/m²/day, with the most common species after aerobic incubation being Aerococcus viridans and Staphylococcus equorum, while Clostridium perfringens and Staphylococcus simulans were the most common species after anaerobic incubation. A total of 28 different species of bacteria and fungi were classifiable as pathogens. In conclusion, the biodiversity in pig farm dust shows a high diversity of bacterial species. However, samples from the same stable section resembled each other, but also different sections within the same farm also resembled each other, thus indicating a high degree of community stability in the dust source. In regards to fungal identification, the biodiversity was observed to be similar between samples from different stable sections and farms, indicating a higher degree of similarities in the mycobiomes found across pig farms studied.

Effect of Lactobacillus plantarum IS-10506 on blood lipopolysaccharide level and immune response in HIV-infected children

BACKGROUND AND OBJECTIVES

HIV enteropathy may cause disruption of the intestinal barrier, leading to a loss of CD4+ T cells, increased intestinal permeability, and microbial translocation. Lactobacillus plantarum IS-10506 has the ability to improve gut barrier function. This study investigated the effect of L. plantarum IS-10506 on a number of biomarkers of enteropathy-related damage in HIV-infected paediatric patients undergoing antiretroviral therapy (ARV).

MATERIALS AND METHODS

A randomized, double-blind, placebo-controlled study was conducted on 2-18 year-old children, diagnosed as HIV infected according to the WHO 2007 criteria who had received ARV for ≥ 6 months. Subjects were excluded if ARV therapy was discontinued or the patients took probiotics ≥ 2 weeks prior to the study or during the study period. Subjects were randomized into a probiotic group and placebo group. The probiotic group received L. plantarum IS-10506 2.86 × 10¹⁰ cfu/day for 6 days. Blood lipopolysaccharide (LPS) level, serum CD4+ T cell count, serum CD8+ T cell count, CD4+/CD8+ T cell ratio, and faecal sIgA level were assessed as biomarkers.

RESULTS

Twenty-one subjects completed this study. The blood LPS level decreased significantly in the probiotic group (p = 0.001). There was no significant difference in absolute CD4+ T cell count, percent CD4+ cells, absolute CD8+ T cell count, CD4+/CD8+ T cell ratio, or faecal sIgA. No serious adverse events were reported.

CONCLUSION

The probiotic L. plantarum IS-10506 reduced the blood LPS level but showed no effect on the humoral mucosa and systemic immune response in HIV-infected children undergoing ARV therapy.

Pteropus lylei primarily forages in residential areas in Kandal, Cambodia

Bats are the second most species-rich Mammalian order and provide a wide range of ecologically important and economically significant ecosystem services. Nipah virus is a zoonotic emerging infectious disease for which pteropodid bats have been identified as a natural reservoir. In Cambodia, Nipah virus circulation has been reported in Pteropus lylei, but little is known about the spatial distribution of the species and the associated implications for conservation and public health.We deployed Global Positioning System (GPS) collars on 14 P. lylei to study their movements and foraging behavior in Cambodia in 2016. All of the flying foxes were captured from the same roost, and GPS locations were collected for 1 month. The habitats used by each bat were characterized through ground-truthing, and a spatial distribution model was developed of foraging sites.A total of 13,643 valid locations were collected during the study. Our study bats flew approximately 20 km from the roost each night to forage. The maximum distance traveled per night ranged from 6.88-105 km and averaged 28.3 km. Six of the 14 bats visited another roost for at least one night during the study, including one roost located 105 km away.Most foraging locations were in residential areas (53.7%) followed by plantations (26.6%). Our spatial distribution model confirmed that residential areas were the preferred foraging habitat for P. lylei, although our results should be interpreted with caution due to the limited number of individuals studied. Synthesis and applications: Our findings suggest that the use of residential and agricultural habitats by P. lylei may create opportunities for bats to interact with humans and livestock. They also suggest the importance of anthropogenic habitats for conservation of this vulnerable and ecologically important group in Cambodia. Our mapping of the probability of occurrence of foraging sites will help identification of areas where public awareness should be promoted regarding the ecosystem services provided by flying foxes and potential for disease transmission through indirect contact.

Dual RNA-Seq reveals the role of a transcriptional regulator gene in pathogen-host interactions between Pseudomonas plecoglossicida and Epinephelus coioides

Pseudomonas plecoglossicida is a highly pathogenic bacterium for maricultured fish and causes serious losses. A transcriptional regulator gene RK21_RS10315 was found up-regulated during the whole infection process, which was confirmed by qRT-PCR. Five shRNA were designed to silence RK21_RS10315 gene, and the gene expression was reduced up to 96.1%. Compared with the counterpart infected with wild type strain, the infection of RK21_RS10315-RNAi strain resulted in the death time delay, and 90% reduction in mortality of Epinephelus coioides, as well as the alleviation in the symptoms of E. coioides spleen. Moreover, compared with the fish infected with wild type strain, the infection of RK21_RS10315-RNAi strain of P. plecoglossicida resulted in a significant change both in transcriptome of spleen of infected E. coioides and P. plecoglossicida. The KEGG analysis showed that genes of 16 immune pathways in E. coioides were affected by the silence of RK21_RS10315 of P. plecoglossicida. Among them, intestinal immune network for IgA production pathway and leukocyte transendothelial migration pathway were more prominent than other pathways. 19 euk-DEMs in these immune pathways had varying degrees of correlation with 19 pro-DEMs, and the expression of ipxA, grpE, yhbJ, truD and suhB from 19 pro-DEMs were predicted more related to RK21_RS10315 in P. plecoglossicida.

Typhus Group Rickettsiosis, Germany, 2010-20171

Typhus group rickettsiosis is caused by the vectorborne bacteria Rickettsia typhi and R. prowazekii. R. typhi, which causes murine typhus, the less severe endemic form of typhus, is transmitted by fleas; R. prowazekii, which causes the severe epidemic form of typhus, is transmitted by body lice. To examine the immunology of human infection with typhus group rickettsiae, we retrospectively reviewed clinical signs and symptoms, laboratory changes, and travel destinations of 28 patients who had typhus group rickettsiosis diagnosed by the German Reference Center for Tropical Pathogens, Hamburg, Germany, during 2010-2017. Immunofluorescence assays of follow-up serum samples indicated simultaneous seroconversion of IgM, IgA, and IgG or concurrence in the first serum sample. Cytokine levels peaked during the second week of infection, coinciding with organ dysfunction and seroconversion. For 3 patients, R. typhi was detected by species-specific nested quantitative PCR. For all 28 patients, R. typhi was the most likely causative pathogen.

Enhanced lipid extraction from oleaginous yeast biomass using ultrasound assisted extraction: A greener and scalable process

Soaring demand for alternative fuels has been gaining wide interest due to depletion of conventional fuel, increasing petroleum prices and greenhouse gas emissions. Biodiesel, an alternative fuel, derived from oleaginous microbes has been promising because of short incubation time and easy to scale up. Oleaginous yeast Trichosporon sp. is capable of utilizing glycerol and agro-residues for enhanced lipid synthesis. Lipid extraction from Trichosporon sp. biomass showed highest lipid content with ultrasonic assisted extraction (43 ± 0.33%, w/w) coupled with process parameters than the conventional Soxhlet (30 ± 0.28%, w/w) and Binary solvent [choloroform:methanol, (2:1, v/v)] methods (36 ± 0.38%, w/w), respectively. The standardized process parameters of ultrasonic assisted extraction coupled with chloroform/methanol solvent system resulted 95-97% of conversion efficiency in 20 min at 30 °C with a frequency of 50 Hz and 2800 W power, respectively. Enzymatic transesterification of yeast biomass lipid obtained 85% of fatty acid methyl esters that are predominant with oleic acid methyl ester followed by palmitic and stearic acid methyl esters, respectively. These results substantiate that the ultrasonic assisted extraction is a potential green extraction technique that had reduced time, energy and solvent consumption without compromising on lipid quality. Deploying this green extraction technique could make the biodiesel production process inexpensive and eco-friendly.

The hippo pathway effector Yes-associated protein promotes epithelial proliferation and remodeling in chronic rhinosinusitis with nasal polyps

BACKGROUND

Hippo-Yes-associated protein (YAP) pathway plays an important role in epithelial cell proliferation and development. However, its possible role in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unknown. We aim to investigate it on nasal epithelial proliferation and remodeling in CRSwNP.

METHODS

The expressions of hippo pathway components as well as Ki-67 and E-cadherin in the sinonasal mucosa and nasal epithelial cells were analyzed in 14 controls, 14 eosinophilic CRSwNP, and 14 noneosinophilic CRSwNP. Nasal epithelial cells from 6 controls, 6 eosinophilic CRSwNP, and 6 noneosinophilic CRSwNP were cultured and treated with lipopolysaccharide (LPS), Poly(I:C), or a selective YAP inhibitor verteporfin (VP).

RESULTS

The hippo pathway components MST1, LATS1/2, YAP, and TEAD1 were increased in both eosinophilic and noneosinophilic CRSwNP, particularly in nasal epithelial cells, along with upregulation of Ki-67 and downregulation of E-cadherin. The mRNA levels of YAP positively correlated with the Ki-67 mRNA levels, and negatively associated with the E-cadherin mRNA levels in polyp tissues and epithelial cells from nasal polyps (NPECs). LPS and Poly(I:C) upregulated the YAP expression in nasal epithelial cells accompanied by increased TEAD1 and Ki-67 expression. Conversely, YAP inhibition by VP decreased TEAD1 and Ki-67 expression in NPECs.

CONCLUSIONS

Hippo pathway components are abnormally upregulated in NPECs, and its effector YAP promotes nasal epithelial cells proliferation and remodeling in CRSwNP. It provides a rationale to explore inhibition of YAP as a novel therapeutic strategy for reducing the epithelial proliferation and remodeling in CRSwNP.

The yield of monitoring adenovirus in pediatric hematopoietic stem cell transplant patients

Human adenovirus (HAdV) is recognized as a serious pathogen after allogeneic hematopoietic stem cell transplantation (HSCT), causing morbidity and mortality. Currently, there is no universal agreement regarding routine HAdV surveillance after HSCT. We assessed the impact of HAdV weekly monitoring by polymerase chain reaction (PCR) on HAdV viremia rates and the risk factors that influence survival. Three-hundred and fifty-six pediatric allogeneic HSCT were done between 2007 and 2015. Until July 2011, HAdV testing was performed based on clinical suspicion (cohort 1, n = 175) and from August 2011, weekly blood-HAdV monitoring was done (cohort 2, n = 181) until day +100. Twenty-three patients (4 [2.3%] from cohort 1 and 19 [10.5%] from cohort 2, p = .001) were found with HAdV viremia and seven of them died. Both cohorts had a similar incidence of HAdV-associated mortality (3/175; 1.7% in cohort 1 and 4/181; 2.2% in cohort 2). Respiratory failure was the cause of death in all patients. Clinical symptoms appeared prior to or within 5 days of HAdV detection in cohort 2. In summary, weekly monitoring was associated with higher detection of HAdV. The study could not assess survival benefit due to small numbers of HAdV-positive cases. In many instances, symptoms occurred with the development of positive HAdV blood PCR results and hence, symptomatology could have triggered the test. Future studies are needed to provide data that help establishing a uniform approach for regular monitoring of HAdV post-transplant.

Monitoring the antimicrobial susceptibility of Gram-negative organisms involved in intraabdominal and urinary tract infections recovered during the SMART study (Spain, 2016 and 2017)

OBJECTIVE

Continuous antimicrobial resistance surveillance is recommended by Public Health authorities. We up-dated data from the SMART (Study for Monitoring Antimicrobial Resistance Trends) surveillance study in Spain.

METHODS

The antimicrobial susceptibility data and extended-spectrum beta-lactamase (ESBL) production in isolates recovered from intra-abdominal (IAI) (n=1,429) and urinary tract (UTI) (n=937) infections during the 2016- 2017 SMART study in 10 Spanish hospitals were analysed.

RESULTS

Escherichia coli was the most frequently microorganism isolated (48.3% and 53.7%) followed by Klebsiella spp. (11.5% and 21.9%) in IAIs and UTIs, respectively. Figures for Pseudomonas aeruginosa were 9.0% and 6.1%, being more frequently recovered from patients with nosocomial infections. Overall, 9.9% (IAI) and 14.0% (UTI) of E. coli, Klebsiella spp. and Proteus mirabilis isolates were ESBL-producers, being Klebsiella pneumoniae (34.5%) from UTI of nosocomial origin the most frequent. ESBL-producers were higher in patients >60 years in both IAIs and UTIs. As in previous years, amikacin (96.3%-100% susceptibility), ertapenem (84.2%-100%) and imipenem (70.3%- 100%) were the most active antimicrobials tested among Enterobacterales species. The activity of amoxicillin-clavulanic, piperacillin-tazobactam, and ciprofloxacin susceptibility was lower, particularly among ESBL-producers. Ertapenem susceptibility (88.9%-100%) was retained in ESBL-E. coli isolates that were resistant to these antimicrobials but decreased (28.6%-100%) in similar isolates of K. pneumoniae.

CONCLUSIONS

Continuous antimicrobial resistance surveillance from the SMART study reveals overall maintenance of ESBL-producers in Spain, although with higher presence in isolates from UTIs than from IAIs. Moreover, ertapenem activity was high in E. coli irrespective of ESBL production but decreased in K. pneumoniae, particularly among ESBL-producers.

Transposon mutagenesis in Pseudomonas fluorescens reveals genes involved in blue pigment production and antioxidant protection

Pseudomonas fluorescens Ps_77 is a blue-pigmenting strain able to cause food product discoloration, causing relevant economic losses especially in the dairy industry. Unlike non-pigmenting P. fluorescens, blue pigmenting strains previously were shown to carry a genomic region that includes homologs of trpABCDF genes, pointing at a possible role of the tryptophan biosynthetic pathway in production of the pigment. Here, we employ random mutagenesis to first identify the genes involved in blue-pigment production in P. fluorescens Ps_77 and second to investigate the biological function of the blue pigment. Genetic analyses based on the mapping of the random insertions allowed the identification of eight genes involved in pigment production, including the second copy of trpB (trpB_1) gene. Phenotypic characterization of Ps_77 white mutants demonstrated that the blue pigment increases oxidative-stress resistance. Indeed, while Ps_77 was growing at a normal rate in presence of 5 mM of H₂O₂, white mutants were completely inhibited. The antioxidative protection is not available for non-producing bacteria in co-culture with Ps_77.

Domestic canines do not display evidence of gut microbial dysbiosis in the presence of Clostridioides (Clostridium) difficile, despite cellular susceptibility to its toxins

Clostridioides difficile infection (CDI) is an emerging public health threat and C. difficile is the most common cause of antimicrobial-associated diarrhea worldwide and the leading cause of hospital-associated infections in the US, yet the burden of community-acquired infections (CAI) is poorly understood. Characterizing C. difficile isolated from canines is important for understanding the role that canines may play in CAI. In addition, several studies have suggested that canines carry toxigenic C. difficile asymptomatically, which may imply that there are mechanisms responsible for resistance to CDI in canines that could be exploited to help combat human CDI. To assess the virulence potential of canine-derived C. difficile, we tested whether toxins TcdA and TcdB (hereafter toxins) derived from a canine isolate were capable of causing tight junction disruptions to colonic epithelial cells. Additionally, we addressed whether major differences exist between human and canine cells regarding C. difficile pathogenicity by exposing them to identical toxins. We then examined the canine gut microbiome associated with C. difficile carriage using 16S rRNA gene sequencing and searched for deviations from homeostasis as an indicator of CDI. Finally, we queried 16S rRNA gene sequences for bacterial taxa that may be associated with resistance to CDI in canines. Clostridioides difficile isolated from a canine produced toxins that reduced tight junction integrity in both human and canine cells in vitro. However, canine guts were not dysbiotic in the presence of C. difficile. These findings support asymptomatic carriage in canines and, furthermore, suggest that there are features of the gut microbiome and/or a canine-specific immune response that may protect canines against CDI. We identified two biologically relevant bacteria that may aid in CDI resistance in canines: 1) Clostridium hiranonis, which synthesizes secondary bile acids that have been shown to provide resistance to CDI in mice; and 2) Sphingobacterium faecium, which produces sphingophospholipids that may be associated with regulating homeostasis in the canine gut. Our findings suggest that canines may be cryptic reservoirs for C. difficile and, furthermore, that mechanisms of CDI resistance in the canine gut could provide insights into targeted therapeutics for human CDI.

Human Pasteurella multocida Infection with Likely Zoonotic Transmission from a Pet Dog, Spain

We report a case of urinary tract infection caused by an unusual genotype (sequence type 211) of Pasteurella multocida associated with human infection. Molecular genetic analysis of P. multocida isolates obtained from the human patient and his pet strongly suggests a zoonotic transmission of this bacterium.

Bacterial biofilm formation on indwelling urethral catheters

Urethral catheters are the most commonly deployed medical devices and used to manage a wide range of conditions in both hospital and community care settings. The use of long-term catheterization, where the catheter remains in place for a period >28 days remains common, and the care of these patients is often undermined by the acquisition of infections and formation of biofilms on catheter surfaces. Particular problems arise from colonization with urease-producing species such as Proteus mirabilis, which form unusual crystalline biofilms that encrust catheter surfaces and block urine flow. Encrustation and blockage often lead to a range of serious clinical complications and emergency hospital referrals in long-term catheterized patients. Here we review current understanding of bacterial biofilm formation on urethral catheters, with a focus on crystalline biofilm formation by P. mirabilis, as well as approaches that may be used to control biofilm formation on these devices. SIGNIFICANCE AND IMPACT OF THE STUDY: Urinary catheters are the most commonly used medical devices in many healthcare systems, but their use predisposes to infection and provide ideal conditions for bacterial biofilm formation. Patients managed by long-term urethral catheterization are particularly vulnerable to biofilm-related infections, with crystalline biofilm formation by urease producing species frequently leading to catheter blockage and other serious clinical complications. This review considers current knowledge regarding biofilm formation on urethral catheters, and possible strategies for their control.

Widespread Treponema pallidum Infection in Nonhuman Primates, Tanzania

We investigated Treponema pallidum infection in 8 nonhuman primate species (289 animals) in Tanzania during 2015-2017. We used a serologic treponemal test to detect antibodies against the bacterium. Infection was further confirmed from tissue samples of skin-ulcerated animals by 3 independent PCRs (polA, tp47, and TP_0619). Our findings indicate that T. pallidum infection is geographically widespread in Tanzania and occurs in several species (olive baboons, yellow baboons, vervet monkeys, and blue monkeys). We found the bacterium at 11 of 14 investigated geographic locations. Anogenital ulceration was the most common clinical manifestation; orofacial lesions also were observed. Molecular data show that nonhuman primates in Tanzania are most likely infected with T. pallidum subsp. pertenue-like strains, which could have implications for human yaws eradication.

Astrovirus evolution and emergence

Astroviruses are small, non-enveloped, positive-sense, single-stranded RNA viruses that belong to the Astroviridae family. Astroviruses infect diverse hosts and are typically associated with gastrointestinal illness; although disease can range from asymptomatic to encephalitis depending on the host and viral genotype. Astroviruses have high genetic variability due to an error prone polymerase and frequent recombination events between strains. Once thought to be species specific, recent evidence suggests astroviruses can spread between different host species, although the frequency with which this occurs and the restrictions that regulate the process are unknown. Recombination events can lead to drastic evolutionary changes and contribute to cross-species transmission events. This work reviews the current state of research on astrovirus evolution and emergence, especially as it relates to cross-species transmission and recombination of astroviruses.

Complexities in understanding antimicrobial resistance across domesticated animal, human, and environmental systems

Antimicrobial resistance (AMR) is a significant threat to both human and animal health. The spread of AMR bacteria and genes across systems can occur through a myriad of pathways, both related and unrelated to agriculture, including via wastewater, soils, manure applications, direct exchange between humans and animals, and food exposure. Tracing origins and drivers of AMR bacteria and genes is challenging due to the array of contexts and the complexity of interactions overlapping health practice, microbiology, genetics, applied science and engineering, as well as social and human factors. Critically assessing the diverse and sometimes contradictory AMR literature is a valuable step in identifying tractable mitigation options to stem AMR spread. In this article we review research on the nonfoodborne spread of AMR, with a focus on domesticated animals and the environment and possible exposures to humans. Attention is especially placed on delineating possible sources and causes of AMR bacterial phenotypes, including underpinning the genetics important to human and animal health.

The application of antibiotics in broiler production and the resulting antibiotic resistance in Escherichia coli: A global overview

The increase in antibiotic resistance is a global concern for human and animal health. Resistant microorganisms can spread between food-producing animals and humans. The objective of this review was to identify the type and amount of antibiotics used in poultry production and the level of antibiotic resistance in Escherichia coli isolated from broilers. Isolate information was obtained from national monitoring programs and research studies conducted in large poultry-producing regions: US, China, Brazil, and countries of EU-Poland, United Kingdom, Germany, France, and Spain. The survey results clearly display the absence of a harmonized approach in the monitoring of antibiotics per animal species and the evaluation of resistances using the same methodology. There is no public long-term quantitative data available targeting the amount of antibiotics used in poultry, with the exception of France. Data on antibiotic-resistant E. coli are available for most regions but detection of resistance and number of isolates in each study differs among regions; therefore, statistical evaluation was not possible. Data from France indicate that the decreased use of tetracyclines leads to a reduction in the detected resistance rates. The fluoroquinolones, third-generation cephalosporins, macrolides, and polymyxins ("highest priority critically important" antibiotics for human medicine according to WHO) are approved for use in large poultry-producing regions, with the exception of fluoroquinolones in the US and cephalosporins in the EU. The approval of cephalosporins in China could not be evaluated. Tetracyclines, aminoglycosides, sulfonamides, and penicillins are registered for use in poultry in all evaluated countries. The average resistance rates in E. coli to representatives of these antibiotic classes are higher than 40% in all countries, with the exception of ampicillin in the US. The resistance rates to fluoroquinolones and quinolones in the US, where fluoroquinolones are not registered for use, are below 5%, while the average of resistant E. coli is above 40% in Brazil, China, and EU, where use of fluoroquinolones is legalized. However, banning of fluoroquinolones and quinolones has not totally eliminated the occurrence of resistant populations.

Adenovirus-associated antibodies in UK cohort of hemophilia patients: A seroprevalence study of the presence of adenovirus-associated virus vector-serotypes AAV5 and AAV8 neutralizing activity and antibodies in patients with hemophilia A

BACKGROUND

Current treatment for severe hemophilia A is replacement of deficient factor. Although replacement therapy has improved life expectancy and quality, limitations include frequent infusions and high costs. Gene therapy is a potential alternative that utilizes an adeno-associated virus (AAV) vector containing the human genetic code for factor 8 (FVIII) that transduces the liver, enabling endogenous production of FVIII. Individuals with preexisting immunity to AAV serotypes may be less likely to benefit from this treatment.

OBJECTIVES

This study measured seroprevalence of antibodies to AAV5 and 8 in an UK adult hemophilia A cohort.

PATIENTS/METHODS

Patients were recruited from seven hemophilia centres in the UK. Citrated plasma samples from 100 patients were tested for preexisting activities against AAV5 and 8 using AAV transduction inhibition and total antibodies assays.

RESULTS

Twent-one percent of patients had antibodies against AAV5 and 23% had antibodies against AAV8. Twenty-five percent and 38% of patients exhibited inhibitors of AAV5 or AAV8 cellular transduction respectively. Overall seroprevalence using either assay against AAV5 was 30% and against AAV8 was 40% in this cohort of hemophilia A patients. Seropositivity for both AAV5 and AAV8 was seen in 24% of participants.

CONCLUSIONS

Screening for preexisting immunity may be important in identifying patients most likely to benefit from gene therapy. Clinical studies may be needed to evaluate the impact of preexisting immunity on the safety and efficacy of AAV mediated gene therapy.

Clinical evaluation of multiplex RT-PCR assays for the detection of influenza A/B and respiratory syncytial virus using a high throughput system

BACKGROUND

Lower respiratory tract infections are a major threat to public health systems worldwide, with RSV and influenza being the main agents causing hospitalization. In outbreak situations, high-volume respiratory testing is needed. In this study, we evaluated the analytical and clinical performance of a pre-designed primer/probe set for the simultaneous multiplex detection of both viruses on a high-throughput platform, the cobas^® 6800, using the "open channel" of the system for integration of lab-developed assays for the detection of influenza and RSV.

RESULTS

Using the influenza/RSV qPCR Assay with swabs, LoD (95%) in TCID50/mL for influenza-A was 0.009, influenza-B 0.003, RSV-A 0.202, and RSV-B 0.009. Inter-run variability (3xLoD) was low (<1 Ct for all targets). Of 371 clinical respiratory specimens analyzed, results were concordant for 358 samples. The calculated sensitivity and specificity of the assay were 98.3% and 98.4% for Flu-A, 100% and 98.5% for Flu-B, and 98.6% and 99.7% for RSV. All quality assessment panel specimens (N = 63, including avian influenza strains) were correctly identified. None of the tested microorganisms showed cross-reactivity.

CONCLUSION

Compared with CE-IVD assays, the assay evaluated here showed good analytical and clinical sensitivity and specificity with broad coverage of different virus strains. It offers high-throughput capacity with low hands-on time, facilitating the laboratory management of large respiratory outbreaks.

Potential role of cancer stem cells as biomarkers and therapeutic targets in cervical cancer

BACKGROUND

Eradicating cancer stem cells (CSCs) that are termed as the "beating heart" of various malignant tumors, including cervical cancer, holds great importance in cancer therapeutics. CSCs not only confer chemo-radio resistance but also play an important role in tumor metastasis and thereby pose a potential barrier for the cure of cervical cancer. Cervical cancer, a common malignancy among females, is associated with high morbidity and mortality rates, and the study on CSCs residing in the niche is promising.

RECENT FINDINGS

Biomarker approach to screen the cervical CSCs has gained impetus since the past decade. Progress in identification and characterization of the stem cell biomarkers has led to many insights. For the diagnostic purpose, several biomarkers like viral (HPV16), stem cell markers, transcription factors (viz, SOX2, OCT 4, and c-Myc), and CSC surface markers (viz, ALDH1 and CD44) have been identified. The research so far has been directed to study the CSC stemness and demonstrates various gene expression signatures in cervical CSCs. Such studies hold a potential to improve diagnostic accuracy and predict therapeutic response and clinical outcome in patients.

CONCLUSIONS

Stem cell biomarkers have been validated and their therapeutic targets are being developed as "strategies to improve therapeutic ratio in personalized medicine." This review gives a brief overview of the cervical CSC biomarkers, their current and future diagnostic, prognostic, and therapeutic potential.

Attitude toward livestock farming does not influence the earlier observed association between proximity to goat farms and self-reported pneumonia

Attitudes toward environmental risks may be a source of bias in environmental health studies because concerns about environmental hazards may influence self-reported outcomes.

OBJECTIVE

The main aim was to assess whether earlier observed associations between proximity to goat farms and self-reported pneumonia were biased by participants' attitude toward farming.

METHODS

We developed an attitude-score for 2,457 participants of the Dutch Livestock Farming and Neighbouring Residents' Health Study (veehouderij en gezondheid omwonenden) by factor analysis of 13 questionnaire items related to attitude toward livestock farming. Linear regression analysis was used to assess associations between attitude and potential determinants. The effect of attitude on the association between goat farm proximity and pneumonia was analyzed by evaluating (1) misclassification of the outcome, (2) effect modification by attitude, and (3) exclusion of participants reporting health problems due to farms in their environment.

RESULTS

In general, the study population had a positive attitude toward farming, especially if participants were more familiar with farming. Older participants, females, ex-smokers, and higher-educated individuals had a more negative attitude. Both self-reported respiratory symptoms and exposure to livestock farms were associated with a more negative attitude. Misclassification of self-reported pneumonia was nondifferential with regard to participants' attitude. Furthermore, no indication was found that the association between proximity to goat farms and pneumonia was modified by attitude. Excluding subjects who attributed their health symptoms to livestock farms did also not change the association.

CONCLUSIONS

The association between goat farm proximity and pneumonia was not substantially biased by study participants' attitude toward livestock farming.

Evaluation and Comparison of Two Different Mouthwashes on Frictional Resistance Between Orthodontic Bracket and Archwire: An in Vitro Study

Aims: This study aimed to evaluate and compare the effect of tea tree oil (TTO) mouthwash and chlorhexidine (CHX) mouthwash on frictional resistance.

Settings and Design: In vitro.

Materials and Methods: In total, 60 extracted premolars were mounted on a custom-made acrylic fixture. These 60 premolars were randomly divided into 3 groups of 20 each, on which 0.022″ × 0.028″ slot MBT stainless steel brackets were bonded and 0.019″ × 0.025″ rectangular stainless steel wire was ligated with an elastomeric module. The 3 groups included a control group where the samples were immersed in artificial saliva and 2 experimental groups immersed in 0.2% CHX and TTO mouthwash, respectively, for 1.5 hours. Postimmersion static frictional resistance was evaluated on a universal testing machine at crosshead speed of 0.5 mm/min.

Statistical Analysis Used: Tukey’s post hoc procedure.

Results: This study showed a statistically significant difference in the frictional resistance between saliva and CHX groups and CHX and TTO groups ( P < .05). No statistically significant difference was observed between saliva and TTO groups ( P > .05). The frictional resistance was more in the CHX mouthwash group than in the TTO mouthwash group.

Conclusions: Frictional resistance was lesser in the TTO mouthwash than in the CHX mouthwash. Based on this result, TTO mouthwash can be used instead of CHX mouthwash as an oral hygiene aid in patients with orthodontic treatments.

Pediatric bloodstream infections in metropolitan Australia

BACKGROUND

Bloodstream infections (BSIs) cause significant morbidity and mortality of children worldwide. The aim of this study was to investigate BSI in children and determine the identity of causative organism and their susceptibility patterns in a metropolitan public hospital in Australia.

METHODS

We retrospectively reviewed children aged 0-16 years admitted to a public hospital from January 1, 2010 to August 31, 2014 inclusive, and whose blood cultures revealed bacteraemia. Data were collected regarding patient demographics, species of bacteria isolated, antimicrobial susceptibility of these isolates, and clinical outcomes.

RESULTS

Out of 96 patients with BSI, 55 (57.3%) were males. The median age was 3.35 years (IQR 0.44-7.46), and there were 2 mortalities. Common sites of infection were the respiratory tract (16.6%, n = 16), bone and joints (15.6%, n = 15) and the urinary tract (11.5%, n = 11). The most frequent isolates were Staphylococcus aureus (27.0%), Escherichia coli (14.0%) and Streptococcus pneumoniae (12.0%). Whilst most bacterial isolates displayed susceptibility (> 90%) to common antimicrobial agents, only 57.1% (8/14) of Escherichia coli isolates were susceptible to ampicillin and 58.3% (7/12) were susceptible to co-trimoxazole.

CONCLUSIONS

Gram-positive bacteria accounted for the majority of pediatric BSIs, of which invasive pneumococcal disease remains a noteworthy cause. The majority of isolates, except Escherichia coli, were susceptible to commonly used antimicrobials. This study confirms the knowledge of high rates of resistance of Escherichia coli to ampicillin. Therefore, empirical treatment should still include gentamicin. Monitoring of resistance patterns is warranted to ensure that antibiotic therapy remains appropriate.

Risk of bacterial exposure to the endoscopist's face during endoscopy

BACKGROUND AND AIMS

Nonuniversal use of facial protection during endoscopy may place endoscopists at risk of exposure to blood and body fluids; however, the frequency of exposure is unknown.

METHODS

A prospective 6-month study of 4 gastroenterologists using a face shield during endoscopy was undertaken. The face shield was swabbed in a standardized fashion before and at the end of the session. Controls included pre- and post-swabs of face shields placed on the (1) endoscopy suite wall, (2) remote patient intake bay wall, and (3) after deliberate contamination with a colonoscope immediately after colonoscopy. The swabs were cultured for 48 hours, and growth was reported as no growth or by number of colony-forming units (CFUs). The groups were compared for +CFU rate and CFU number.

RESULTS

A total of 1100 procedures were performed in 239 endoscopy sessions. The +CFU rate in the pre-endoscopy groups (2%-4.8%, not significant) was significantly lower than the postendoscopist face shield (45.8%, P < .001) and endoscopy suite wall groups (21.4%, P < .001), respectively. Using a cut-off of >15 CFUs as an indicator of definite exposure, the occurrence rate was 5.6 per 100 half days of endoscopy to the endoscopist's face and 3.4 per 100 half days of endoscopy 6 feet away.

CONCLUSIONS

This is the first study to quantify the rate of unrecognized exposure to the endoscopist's face to potentially infectious biologic samples during endoscopy (5.6/100 days of endoscopy). This exposure may result in transmission of infectious diseases. As such, we recommend the use of universal facial protection during GI endoscopy.

Preventing legionellosis outbreaks by a quick detection of airborne Legionella pneumophila

Legionellosis is a severe pneumonic infection caused by inhaling bacteria of the genus Legionella. Most cases reported in the USA and Europe are associated with the species Legionella pneumophila. This Gram-negative bacterium can survive within a wide spectrum of temperatures, and be transmitted via aerosols from multiple aquatic sources: fountains, thermal spas and other water systems. Although the PCR is one of the most popular methods to verify its presence in environmental or clinical samples, the direct application of this technique to ambient air samples is unusual because of the scarce material in the specimens. Here, we have developed a two-PCR assay, carried out over the V3 and V5 hypervariable regions of the 16S rRNA gene, to detect specifically the pathogenic bacteria Legionella pneumophila in outdoor air samples with low concentration of DNA. The application of this protocol does not require culture and retrieves quick results to activate the corresponding public alerts to prevent legionellosis outbreaks.